Product specifications
            euroquartz
X21-W crystals are ultra-miniature surface-mount mount crystals. The crystals have a gold plated ceramic base with a seam welded metal lid providing a stable crystal with very low ageing. The rugged construction ensures that this crystal has high shock and vibration resistance. The crystal has been optimized for WI-Fi applications: Bluetooth/ Bluetooth Low Energy (BLE), Bluetooth Smart, Zigbee, ISM, Wi-Fi / WLAN, LPWAN and others.
Specification: 
Standard Frequencies*: 16.0, 19.2, 20.0, 24.0, 25.0,  26.0, 27.120, 30.0, 32.0, 37.40,  38.40, 40.0, 48.0, 52.0MHz 
Operating Mode: AT-Cut Fundamental: 
Calibration Tolerance at 25ºC:  ±10ppm 
Frequency stability -20° to +70°C ±10ppm -40° to +85°C ±15ppm -40° to +105°C ±30ppm 
Storage Temperature:  -50°~+105°C 
Equivalent Series Resistance: 
Shunt Capacitance (C0):  2pF to 4pF typical, 5pF maximum
 Load Capacitance (CL):  Series or from 10pF to 32pF
Ageing:  <±ppm per first year at +25°C Drive level:  100 µW maximum 
Reflow Soldering:  10s maximum at 260°C twice  or 180s at 230°C, once.
 Packaging:  12mm EIA tape and reel